[LUA-Awesome] Can i use $XDG_XY_DIR inside a lua script?

Heyas

I'm a fan of AwesomeWM, but i had failed to learn lua, though, i'm quite satisfied with the cofniguration i have by now.

Either way, i'd like to know if i could 'call' those XDG_XY_DIR variables which are located on my linux ~/.config/user-dirs.dirs.

While to call scripts i use (copy-changed):

{ "BG: NASA iotd", "sh " .. awful.util.getdir("config") .. "/scripts/nasaBackground.sh",  },

I'm currently trying to open the project-container-folder like this:

menuscripttools = {
	    { "------",},
	    { "projects", files .. "$XDG_PROJECTS_DIR" },
	}

The menu is displayed properly, however, clicking on the according menu entry "projects", results in no activity...

Do i need to call a script in order to use $XDG_PROJECTS_DIR?
And if so, how could i get the use of the 'set' filenamager 'files' within the script to be called?
Or could i grep (or alike) the required value somehow?
Or is there a way to 'source' ~/.config/user-dirs.dirs within LUA?

I know there are 'bashets' but since i dont need a datastream just an execution (opening a folder), that seems a little too much..

Any ideas or thoughts?
Thank you.